WiMAX is designed for "last mile" point to multi-point solutions. Like WiFi, it can support multi-megabit throughput. However consider the advantages of WiMAX:
WiMAX has an inherent Quality of Service protocol and is designed to operate over longer distances compared to WiFi.
WiMAX can operate in the unlicensed 5.1-5.8GHz spectrum similar to WiFi but it can also operate in the 3.3-3.8GHz licensed spectrum. The 3GHz licensed spectrum allows for higher data rates and can transmit over longer distances since there is no interference from competing services.